In recent years, concern has grown over the amount of water that is wasted each year in the home. It has been observed, for example, that it is not always necessary to completely drain a bathroom flush tank. As a result, a number of devices now exist that reduce the amount of water used in a typical bathroom flush tank.
One such device is a plastic float that surrounds an overflow pipe already installed in the flush tank. A plunger extends downward from the float an adjustable distance. In operation, when the flush outlet cover is raised, thereby allowing water to flow out of the tank, the float drops with the water level until the plunger presses against the flush outlet cover, thereby forcing the cover over the water outlet and preventing further water loss from the tank.
This device succeeds in saving water in a relatively simple manner. No complex installation is required, and manufacturing costs of the device are relatively inexpensive. However, it does not allow the user of the flush tank a choice between a full or partial flush, as is sometimes necessary depending upon the amount and type of waste materials to be flushed. For instance, solid waste requires more water to be effectively flushed into the sewage system than does liquid waste.
A number of dual flush devices exist that provide a choice between a full tank flush, whereby the entire amount of water in the tank is expelled, or a partial tank flush, whereby a partial amount of water in the tank is expelled. Unfortunately, these devices typically require the installation of a new, relatively complex flush tank valve and alterations to the flush actuation arm. As a result, the typical homeowner finds it both expensive and difficult to install such devices into his flush tanks, and, consequently, will often not bother to install them.
Clearly, then, there is a need for a relatively simple device that is easy to install in the typical flush tank, is relatively inexpensive to manufacture, and provides a choice between two different flush amounts. The present invention fulfills these needs and provides further related advantages.